Generally the prior art reveals two types of tools for installing decking or sheathing--devices based on spikes or prongs to engage the tool with supporting members and devices based on a mechanism for clamping the tool to supporting members. Illustrative of the prong devices are:
U.S. Pat. No. 3,524,623 to Campbell where the tool has prongs that dig into the subflooring in order to exert force on the boards being laid. U.S. Pat. No. 3,331,584 to Schwartz reveals a cam-lever type floor jack that pivots about spiked members that dig into the underside of the joist. U.S. Pat. No. 3,203,668 to Pitsenbarger relates to a flooring jack for installing tongue and groove boards. This device relies on a pointed end of the tool being driven into the subfloor and supplying leverage for a push rod. U.S. Pat. No. 2,823,011 to Jones shows a sliding tool that is anchored to a stud or similar member with a prong.
Illustrative of the clamping devices are:
U.S. Pat. No. 2,780,437 that discloses a device that clamps to the joist. U.S. Pat. No. 2,625,368 to Warner reveals a jack that also depends on being clamped to the joist. U.S. Pat. No. 2,351,691 to Mansir relates to a lumber puller that relies on cams to engage and clamp the tool to the sides of a joist. U.S. Pat. No. 1,911,705 to McMullan shows a cramp for floorboards that utilizes two dogs to grip the sides of a joist. U.S. Pat. No. 721,681 to Ulrey discloses a flooring clamp that uses pawls to engage the joist from opposite sides and clamp the device thereto. U.S. Pat. No. 32,120 to Clough reveals a clamp-device for laying floorboards.
Generally, the prong or spike type devices do considerable damage to the joist or subfloor with which they are used. As such they mar the wood and create splinters that may be unsightly as well as dangerous on a construction such as an open deck. On the other hand, the clamping devices are mechanically complex and subject to bending and breaking, especially when it is necessary to apply significant force such as might be necessary with a badly warped board.